Casing joint



y H.WAYMEYE R 2,041,037 V CASING JOINT Filed Aug. 22, 1955 may Patented May 19, 1936 UNITED STATES PATENT OFFICE CASING JOINT Henry Waymeyer, Fort Perry, Ky.,

assignor to The Williamson Heater Company, Cincinnati, Ohio, a corporation of Ohio Application August 22, 1935,. Serial No. 37,381 4 Claims. (01. 189-36) This invention relates to a casing joint for furnaces.

An object of the invention is a joint construction for a furnace casing which does not require either rivets or bolts as a fastening means.

Another object of the invention is an interlocking casing-joint which may readily be set up or knocked down.

Furnaces are assembled on the job; the casings, however require time and labor because of the many bolts and rivets necessary to fasten V the casing sections together. Furthermore, in event the castings are in disrepair the casing must be opened thus necessitating the removal of rivets and. bolts. My invention provides for the elimination of rivets or bolts in furnace casing construction, whilst retaining the stability attained by their use.

In the drawing:

Fig. l is a front elevational view of a furnace,

Fig. 2 is a cross sectional view taken on line 2-2 of Fi 1.

Fig. 3 is a perspective view of the two parts of the joint.

Fig. 4 is a top plan view of the joint with the lug in position to be moved into the slot.

Fig. 5 is a top plan view of the joint showing the lug engaged in the slot.

Fig. 6 is a view taken on line 6-43 of Fig. 5.

My joint is illustrated as applied to a furnace 8 having front casing sections 9 and Ill and side sections H and I2. As shown in Fig. 2 the front section has a right angle bend [3 which forms a corner I4 of the furnace. The casing joint 35 I5 may be employed wherever it is desired to interlock sections of casing plates about the furnace castings,

My joint is made as follows:

A sheet metal plate, II, has a longitudinal return bend I6, the end of the sheet being again bent to project outwardly to form a flange H. A longitudinal channel I8 is formed by the flange and the return portion of the bend IS. A number of ways 19 having transverse guide edges 20 and 2| are cut in the flange at spaced intervals, (Fig. 1). A slot 22 is cut in the flange adjacent each of the ways, and has an abutting edge 23 inclined at an angle relative to the longitudinal edge of the flange. The flange is made of a greater width than the return bend portion to provide a greater reenforcing area for the slot and also form an alignment edge for the complementary sheet 9. The complementary sheet metal plate, as 9, has a number of inclined projecting lugs 24 which are spaced along the edge of the plate so as to register with the ways IS. The lugs are formed by stamping a relatively long transverse cut 25 and. a relatively short transverse cut 26, in the edge of the plate and then bending back the metal between the cuts on the inclined line 21, which is of the same inclination as the abutting edge 23 cut in the flange.

Fig. 3 shows the relative position of the interlocking parts preparatory to their engagement. Fig. 4 shows the relative position of parts after the edge portion of the complementary sheet has been received in the channel IS, the lugs 24 having moved their full lateral distance in the ways I9.

Fig. 5 shows the relative position of parts in interlocking relationship, the lugs having been moved longitudinally into the slots 22. In this position the abutting inclined edge 23 of the slot engages the inclined projecting lug 24 firmly. In practice a plurality of the above described lugs 24 would be formed along the edge of the sheet 9 (Fig. l) and a similar number of ways l9 and slots 22 would be formed in the sheet metal plate H, to receive the lugs. All the slots 22, thus formed are positioned below the ways l9 so that when the lugs of sheet 9 are slid into the ways IS the sheet will fall, by force of gravity, to allow the lugs to engage the inclined edge 23 of the slot 22. In this condition the two sheets 9 and. II will remain in interlocking relationship because the lugs engaging the inclined edges of the slots 22 will prevent all longitudinal movement between the joined sheets. The furnace casing thus employing applicants joint would necessarily have vertical sides and be substantially square (as illustrated in Fig. 2). To assemble the casing the front sheet metal plate would first be bolted to the fire door and ash pit door castings in the usual manner. The free edge of this front plate would contain a plurality of ways and slots as already described to receive lugs formed in the edge of plate to be next assembled. The casing is progressively built up by joining complementary sheets until the front plate on the opposite side of the fire door casting has been bolted thereto. To disassemble the casing the sheet metal plate last assembled must be removed first, so that each plate may be lifted and then pulledfrom the plate to which it is assembled. The way .I 9 is constructed much wider than lug 24 to facilitate the alignment of the lugs and the way and their subsequent engagement.

To take the furnace casing apart, the operation is the reverse of that just described. Sheet 9 is raised to bring plurality of lugs 24 to register with ways l9 and sheet 9 is then pulled outwardly from sheet ll thereby disengaging the lugs 24 from the way l9. a

What I claim isi V 1. A furnace casing joint comprising a sheet metal plate having a return bend and an outwardly projecting flange along a longitudinal edge and with the return forming a longitudinal channel; theflangeextending beyond the end of the return edge'and having a plurality of transverse ways out in it and adjacent each of the ways a slot having an inclined edge, a comp le mentary sheet metal plate having a plurality of inclined projecting lugs formed from a large and a small cut in the plate and perpendicular to the longitudinal edge thereof and then bending back the portion between said cuts along an inclined line, the channel being adapted to receive the longitudinal edge portion of the'complementary sheet metal plate whilst the projecting lugs are adapted ;tobe receivable in the ways and then to engage the inclined edges of the slots.

2. A-furnace casing joint comprising a sheet metal plate having a return bend and'an outwardly projecting flangealong a longitudinal edge and with the return forming a longitudinal channel, the flange extendingb'eyond the end of the return'edge and having a plurality of trans- V V verse ways cut in it, and adjacent reach of the ways a'slot having an inclinededge, a complementarysheet' metal plate having a plurality of inclined projecting lugs positioned along a longitudinal edge portion thereof, the channel being adapted to receive the longitudinal edge portion of the complementary sheet metal plate whilst the projecting lugs are adapted to be receivable 7 in the ways and then to engage the inclined edges of the slots. 7 I

3. A furnace casing joint comprising a sheet metal plate having a return bend and an outwardly projecting flange along a longitudinal- V edge and with the return forming a longitudinal channel, a flange having a plurality of transverse ways out in it, and adjacent each of the ways a slot having an inclined edge, a complementary sheet metal plate having a plurality of inclined projecting lugs formed from a large and a small cut in the plate andperpendicular to the longitudinal edge thereof and then bending back the portion between said cuts along an inclined line, the channel being adapted to receive the'longitudinal edge portions of the complementary sheet metal plate whilst the projecting lugs are adapted a to be receivable in'the ways and then to engage the inclined edges of the slots.

4. A'furnace casing joint comprising a sheet metal plate having a return-rbendr-and an outwardly projecting flange along a longitudinal edge and with thereturn forming alongitudinal channel, the flange having a. plurality of; transverse ways out in it, and adjacent each of the ways a slot having an inclined edge, a complementary sheet metal plate having a plurality ofpinclinedc projecting lugs positioned along a longitudinal edge portion thereof, the channel being adapted to receive the'longitudinal edge portion of the complementary sheetv metal plate whilstthe projecting lugs are adapted to be receivable in the ways and then to the slots. c 7 c v HENRY WAYMEYER.

engage the inclined edges; of 

